MSK/Derm Flashcards
What is mitochondrial myopathy?
Ragged red fibers; mitos have impaired oxidative phosphorylation = lactic acid
Where do osteoblasts come from?
mesenchymal stem cells in the periosteum
Hallmarks of multiple myeloma?
Think CRAB: hyperCalcemia Renal involvement Anemia Bone lytic lesions (Il-1, TNF)
Multiple Myeloma: Monoclonal M protein spike
Which nerve causes winged scapula?
long thoracic
What causes muscle atrophy?
protein degradation in the muscle cells
What does the musculocutaneous nerve do?
flex the bicep (lateral brachial plexus)
Which structure is assoc w bullous pemphigoid (no blistering)?
hemidesmosomes (attach BM)
Which structure is assoc w pemphigous vulgaris (blistering)?
desmosomes (attach epidermis to each other)
Hip adductor muscle starts where? and inserts where?
ischium; femur
What is osteonecrosis (avascular necrosis)?
Infarct of bone/BM at femoral head = collapse of bone w/o cartilaginous involvement (non-inflam)
What causes osteonecrosis (avascular necrosis)?
ASEPTIC: Alcoholism, Sickle cell disease, Storage (Gaucher), Exogenous/ Endogenous corticosteroids, Pancreatitis, Trauma, Idiopathic (Legg-Calvé-Perthes disease), Caisson (“the bends”)
Which muscle protrudes the tongue? retracts the tongue?
protrude: genioglossus
retract: hyoglossus
What test can help diagnose psoriatic arthritis?
slit lamp test for anterior uveitis which is assoc w psoriatic arthritis
Injury to the lunate bone typically affects which nerve?
median = carpal tunnel
What 2 symptoms indicate axillary nerve damage?
- impaired shoulder abduction
2. loss of sensation over upper lateral arm
When lifting weights, _____ of motor nerve action potentials increases.
frequency (force summation)
Injury to the scaphoid bone typically leads to what condition??
avascular necrosis owing to retrograde blood supply.
Injury to the hook of hamate typically affects which nerve?
ulnar
Damage to which nerve causes foot drop?
common peroneal (lateral leg)
PED = Peroneal Everts and Dorsiflexes; if injured, foot dropPED.
Damage to which nerve means you cant curl your toes?
tibial (back of leg)
TIP = Tibial Inverts and Plantarflexes; if injured, can’t stand on TIPtoes.
Which nerve is responsible for Trendelenberg Sign?
Superior gluteal (glut med/min) = hip drop contra to lesion
What drug is used to treat acute RA?
celecoxib (esp w GI issues)
Injury to which nerve causes winged scapula?
long thoracic
Pt comes with upper + lower motor weakness, mild ataxia, and opthalmoplegia, what do you think is compressed?
vertebral arteries at C6
What 3 symps would suspect spinal nerve compression at cervical level (eg disc herniation)?
- pain
- burning/tingling
- weak/numb shoulder, arm, or hands
Succinylcholine in burn patients causes what set of ECG changes?
hyperkalemia –> peaked T waves
What is thought to cause Paget Disease of the bone?
paramyxovirus infection of osteoclasts
What is Forchheimer’s sign?
Small, Red papules on the soft palate; caused by Rubella
What is Alkaptonuria (ochronosis)?
deficiency of homogentisate oxidase –> accumulation of homogentisic acid
What are the hallmarks of Alkaptonuria (ochronosis)?
- arthralgias
- bluish-black pigmentation (ochronosis) of ears, nose, cheeks
- urine turns black on prolonged exposure to air
The neurofibromas of NF1 are derived from what structures?
peripheral nerves
What antibiotic is used to treat pustular acne?
tetracycline (bind to 30S and prevent attachment of aminoacyl-tRNA)
What additional manifestation can accompany Klumpke palsy (lower trunk lesion)?
ipsi horner syndrome
What nerve arises anteriorly to the anterior scalene muscle?
Phrenic
Loss of innervation to what muscle causes “waiter’s tip hand”?
Biceps brachii
